Rotation of 4 degrees of FIX



Movement of A chain of IX-bp caused by induced fitting and of IXGD1–46 caused by Mg2+ ions. A, interaction patch for IX-bp (residues 100–110 of IX-bp B chain) is overlaid. Complexed and uncomplexed IX-bp A and B chains are shown in red and green for A and in blue and green for B, respectively. B, hydrophobic and hydrophilic interactions involving Lys22 of IXGD1–46 and Thr62, Lys63, and Glu108 of IX-bp A chain resulting from the movement of the A chain. The surface model was calculated using GRASP (41). This interaction was not observed, formed under Mg2+-free condition. C, Mg2+-bound IXGD1–46/IX-bp complex is shown in red and green, and the Mg2+-free (Ca2+ only) complex is depicted by yellow ribbon representation. Both structures are superimposed as a result of the position of C atoms of IX-bp.

Additional Resources
For additional information, see: Hemophilia